El Nino 2023-2024

[bluewave]

6 minutes ago, 40/70 Benchmark said:

Obviously some of this is due to the warming background.....but @ORH_wxman has pointed out that the NE being warmer than everyone else means we are also due for some colder regression in this area relative to other regions.

More than some is due to warming. Any cold regressions in the future will be tempered by the warmer background state. But we should eventually see another colder winter again. Absent some massive volcanic eruption, a top 10 coldest winter like 76-77 simply isn’t possible anymore in this climate. 

[40/70 Benchmark]

51 minutes ago, bluewave said:

More than some is due to warming. Any cold regressions in the future will be tempered by the warmer background state. But we should eventually see another colder winter again. Absent some massive volcanic eruption, a top 10 coldest winter like 76-77 simply isn’t possible anymore in this climate. 

You aren't getting my point. I am speaking of temperature relative to other regions...not absolute temperature. 

"More than some"...what does that even mean? I'm sorry, the NE being the warmest part of the country over the past several years has nothing to do with global warming AFAIC. The NE being warmer than the NE was two decades ago? Sure.

[roardog]

The winter of 13-14 was a very cold winter over here in the Midwest. I believe northern Minnesota ended up colder than 76-77. Although this was 10 years ago, I think it shows that if you get the pattern to support it, it will still get very cold. Even last winter, parts of North Dakota were several degrees below normal for the winter. That’s a bitter cold winter for an area that’s already cold on average. 

The issue in recent years around here and east to where you guys are is really all about the tropical forcing. Is that due to climate change, a natural cycle or a combination of both? It makes you feel like the WPAC warm pool is due to climate change but it also wouldn’t completely surprise me if it reverses in some fashion at some point.

[40/70 Benchmark]

26 minutes ago, roardog said:

The winter of 13-14 was a very cold winter over here in the Midwest. I believe northern Minnesota ended up colder than 76-77. Although this was 10 years ago, I think it shows that if you get the pattern to support it, it will still get very cold. Even last winter, parts of North Dakota were several degrees below normal for the winter. That’s a bitter cold winter for an area that’s already cold on average. 

The issue in recent years around here and east to where you guys are is really all about the tropical forcing. Is that due to climate change, a natural cycle or a combination of both? It makes you feel like the WPAC warm pool is due to climate change but it also wouldn’t completely surprise me if it reverses in some fashion at some point.

I feel like GW causes us to get stuck in more extreme patterns for longer durations of time....no research, just my anecdotal ob....this can sometimes lead to some extreme cold of duration, like '13-'14 and '14-15'. But more often than not, it means warmth, obviously....so maybe in that sense, the strong of warm NE winters relative to the rest of the nation IS due to GW to some degree, but that isn't permanent. 

[griteater]

VP image for Mar 19 to Jun 19 of this year.  Uplift max in W Pac / Subsidence max in C Amer

 

 

VP image for Jun 19 to Sep 19 of this year.  Uplift max W of Dateline / Subsidence max in far E Pac and W Indian Ocean

 

 

VP image for Jun to Sep for Strong and Super Ninos (ONI) since 1980.  Uplift max E of Dateline / Subsidence max in Indonesia

 

 

VP image for Jun to Sep for Moderate Ninos (ONI) since 1980.  Uplift max near and E of Dateline / Subsidence max in Indonesia and Far E Indian Ocean

 

 

VP image for Jun to Sep for Weak Ninos (ONI) since 1980.  Uplift max near and E of Dateline / Subsidence max in Far W Indian Ocean and E Africa

 

 

VP image for subsequent winter (Nov to Feb) for the same Weak Ninos (ONI) since 1980.  Uplift max near Dateline and Indian Ocean / Subsidence max in the Caribbean  

 

 

Bottom Lines:

1. The low frequency VP pattern (3 months or more) this year hasn't changed much going back to March. 

2. The Jun to Sep VP pattern this year is most similar to Weak El Ninos (ONI) when comparing with all El Ninos since 1980.

3. My guess is that the low frequency VP pattern this winter will be similar to the Weak El Nino winter composite with an uplift max along the Dateline and a subsidence max in the Carribean and South America.

4. My guess is that the MJO will become more active this winter and will play a substantial role in the subseasonal / monthly pattern

5. The persistent and strong subsidence region over C America / Carribean / Gulf of Mexico this year is noteworthy and may have contributed to the extensive summer warmth in AZ/NM/TX/LA.

[GaWx]

2 hours ago, bluewave said:

More than some is due to warming. Any cold regressions in the future will be tempered by the warmer background state. But we should eventually see another colder winter again. Absent some massive volcanic eruption, a top 10 coldest winter like 76-77 simply isn’t possible anymore in this climate. 

 With the globe ~2 F warmer than 77-78, do you think there can still be a winter as cold as just 2F warmer than 77-78? For example:

 Ten coldest Savannah winters since 1875-6:

1977-8: 45.8 (~6BN)

1976-7: 46.0

1957-8: 46.2

1969-70: 46.4

1963-4: 46.6

1962-3: 47.0

1968-9: 47.3

2009-10: 47.8

1980-1: 48.0

2010-1: 48.1

 

 So, if an upcoming Savannah winter were to be 2F warmer than 1977-8, it would be 47.8. That would still be tied for 8th coldest, a top 10 winter.

Aside: Note that 7 of the 8 coldest were during El Niño.

[bluewave]

1 hour ago, 40/70 Benchmark said:

You aren't getting my point. I am speaking of temperature relative to other regions...not absolute temperature. 

"More than some"...what does that even mean? I'm sorry, the NE being the warmest part of the country over the past several years has nothing to do with global warming AFAIC. The NE being warmer than the NE was two decades ago? Sure.

The NE being the warmest part of the country over the last several years has plenty to do with the warming climate. Recent studies found as the WPAC heats up due to continued warming, we get more frequent MJO 4-6 phases which pumps the SE Ridge. Also slowing AMOC linked to warming climate causes warmer waters to pile up in the NW Atlantic. So it shifts the odds to warmer teleconnection patterns for us. Now this doesn’t mean that we won’t see another cold winter in the future. Or that we won’t see a shift to some new MJO state as the planet warms. But there is little doubt that the last 8 record warm seasons has had a robust warming climate signal. 

[40/70 Benchmark]

21 hours ago, 40/70 Benchmark said:

High Confidence in Evolution of ENSO Allows for Shift of Focus to Concurrent Sensible Weather | Eastern Mass Weather

Funny, I came to that same conclusion yesterday using a totally different method....comprising a composite of best summer precip and temp matches.

8 minutes ago, griteater said:

VP image for Mar 19 to Jun 19 of this year.  Uplift max in W Pac / Subsidence max in C Amer

 

 

VP image for Jun 19 to Sep 19 of this year.  Uplift max W of Dateline / Subsidence max in far E Pac and W Indian Ocean

 

 

VP image for Jun to Sep for Strong and Super Ninos (ONI) since 1980.  Uplift max E of Dateline / Subsidence max in Indonesia

 

 

VP image for Jun to Sep for Moderate Ninos (ONI) since 1980.  Uplift max near and E of Dateline / Subsidence max in Indonesia and Far E Indian Ocean

 

 

VP image for Jun to Sep for Weak Ninos (ONI) since 1980.  Uplift max near and E of Dateline / Subsidence max in Far W Indian Ocean and E Africa

 

 

VP image for subsequent winter (Nov to Feb) for the same Weak Ninos (ONI) since 1980.  Uplift max near Dateline and Indian Ocean / Subsidence max in the Caribbean  

 

 

Bottom Lines:

1. The low frequency VP pattern (3 months or more) this year hasn't changed much going back to March. 

2. The Jun to Sep VP pattern this year is most similar to Weak El Ninos (ONI) when comparing with all El Ninos since 1980.

3. My guess is that the low frequency VP pattern this winter will be similar to the Weak El Nino winter composite with an uplift max along the Dateline and a subsidence max in the Carribean and South America.

4. My guess is that the MJO will become more active this winter and will play a substantial role in the subseasonal / monthly pattern

5. The persistent and strong subsidence region over C America / Carribean / Gulf of Mexico this year is noteworthy and may have contributed to the extensive summer warmth in AZ/NM/TX/LA.

 

[40/70 Benchmark]

15 minutes ago, bluewave said:

The NE being the warmest part of the country over the last several years has plenty to do with the warming climate. Recent studies found as the WPAC heats up due to continued warming, we get more frequent MJO 4-6 phases which pumps the SE Ridge. Also slowing AMOC linked to warming climate causes warmer waters to pile up in the NW Atlantic. So it shifts the odds to warmer teleconnection patterns for us. Now this doesn’t mean that we won’t see another cold winter in the future. Or that we won’t see a shift to some new MJO state as the planet warms. But there is little doubt that the last 8 record warm seasons has had a robust warming climate signal. 

I call bullshit on this. I know you are one of those people who attributes every fart to global warming, but if you look at a composite of the previous several winters, from like 2008-2014, we were one of the colder regions...and back then GW had supposedly led to the N PAC warm blob. No one will ever win against an argument like this because its self-sustaining, circular logic. Each change is permanent and due to GW...until it changes, then the change is due to GW and the new state is permanent.

Rinse and repeat.....silly.

I do buy the idea that GW is contributing to and protracting these extreme patterns, but cyclical changes have always existed.

[bluewave]

25 minutes ago, 40/70 Benchmark said:

I call bullshit on this. I know you are one of those people who attributes every fart to global warming, but if you look at a composite of the previous several winters, from like 2008-2014, we were one of the colder regions...and back then GW had supposedly led to the N PAC warm blob. No one will ever win against an argument like this because its self-sustaining, circular logic. Each change is permanent and due to GW...until it changes, then the change is due to GW and the new state is permanent.

Rine and repeat.....silly.

I do buy the idea that GW is contributing to and protracting these extreme patterns, but cyclical changes have always existed.

Off course you call BS since you look for a myriad of excuses to explain your way out of why the seasonal forecasts since 15-16 have all been biased too cold in the Northeast. Not sure why acknowledging that we have shifted into a warmer climate state is so hard for you. Again, this doesn’t mean that we won’t have colder winters at times again in the future. But even the colder run of winters at times from time to time from 02-03 to 14-15 were no match for the winters which were really cold from the late 70s to early 90s. Now if you want to ascribe it to some underlying cycle, the cycle was much colder in the late 70s to early 90s than 02-03 to 14-15. Plus the warming cycle since 15-16 was warmer than any earlier warmer periods by a large degree. So if we eventually swing back to another era like 02-03 to 14-15 in regard to colder winters making a comeback, chances are they won’t be as cold as some of those winters were. 
 

Our coldest Northeast winters since 02-03 were no match  for the cold experienced from the late 70s to early 90s.

 

76-77…..18.4….5th coldest average winter temperature 

77-78…..19.5 ..10th coldest 

93-94….19.7…..11th coldest

78-79….20.7….18th coldest

14-15….20.8….19th coldest

02-03…20.9…20th coldest

13-14….22.1…..29th coldest.

 

 

[GaWx]

OHC per this graph back down to under +1.0 and still falling:

[FPizz]

47 minutes ago, GaWx said:

 With the globe ~2 F warmer than 77-78, do you think there can still be a winter as cold as just 2F warmer than 77-78? For example:

 Ten coldest Savannah winters since 1875-6:

1977-8: 45.8 (~6BN)

1976-7: 46.0

1957-8: 46.2

1969-70: 46.4

1963-4: 46.6

1962-3: 47.0

1968-9: 47.3

2009-10: 47.8

1980-1: 48.0

2010-1: 48.1

 

 So, if an upcoming Savannah winter were to be 2F warmer than 1977-8, it would be 47.8. That would still be tied for 8th coldest, a top 10 winter.

Aside: Note that 7 of the 8 coldest were during El Niño.

2 in the past 13 years up there.  Some would have said that was impossible.

[40/70 Benchmark]

14 minutes ago, bluewave said:

Off course you call BS since you look for a myriad of excuses to explain your way out of why the seasonal forecasts since 15-16 have all been biased too cold in the Northeast. Not sure why acknowledging that we have shifted into a warmer climate state is so hard for you. Again, this doesn’t mean that we won’t have colder winters at times again in the future. But even the colder run of winters at times from time to time from 02-03 to 14-15 were no match for the winters which were really cold from the late 70s to early 90s. Now if you want to ascribe it to some underlying cycle, the cycle was much colder in the late 70s to early 90s than 02-03 to 14-15. Plus the warming cycle since 15-16 was warmer than any earlier warmer periods by a large degree. So if we eventually swing back to another era like 02-03 to 14-15 in regard to colder winters making a comeback, chances are they won’t be as cold as some of those winters were. 
 

Our coldest Northeast winters since 02-03 were no match  for the cold experienced from the late 70s to early 90s.

 

76-77…..18.4….5th coldest average winter temperature 

77-78…..19.5 ..10th coldest 

93-94….19.7…..11th coldest

78-79….20.7….18th coldest

14-15….20.8….19th coldest

02-03…20.9…20th coldest

13-14….22.1…..29th coldest.

 

 

Right......this is why I am about as transparent as humanly possible. How does me asserting that cyclical variations have always taken place explain my bias? Sounds like a deflection like tactic born of an infantile temper tantrum.  But I know you aren't like that....must be global warming?

And let me know again when you are going to take the time to author an outlook and then spend an equal amount of time reporting on your own biases....and you probably won't, so I guess we can attribute that to global warming-

[40/70 Benchmark]

23 minutes ago, bluewave said:

Our coldest Northeast winters since 02-03 were no match for the cold experienced from the late 70s to early 90s.

AGAIN.....no one is debating global warming. What I am debating is the notion that this current global regime that favors warmer NE RELATIVE TO THE REST OF THE NATION is going to become fixed in place permanently. I am not debating the warming in an absolute sense.

BTW, I was also skeptical of the "warm blob" becoming a permanent fixture, and that favored a colder east.

[GaWx]

16 minutes ago, FPizz said:

2 in the past 13 years up there.  Some would have said that was impossible.

Strong variability from winter to winter is not going away. It is just that this variability is from a 2F warmer base vs the 1970s.

[bluewave]

15 minutes ago, 40/70 Benchmark said:

Right......this is why I am about as transparent as humanly possible. How does me asserting that cyclical variations have always taken place explain my bias? Sounds like a deflection like tactic born of an infantile temper tantrum.  But I know you aren't like that....must be global warming?

And let me know again when you are going to take the time to author an outlook and then spend an equal amount of time reporting on your own biases....and you probably won't, so I guess we can attribute that to global warming-

Variations whether you call them cyclical, teleconnections, or oscillations all exist in a warmer climate state than they used to. So they aren’t immune from alterations or adjustments to reflect the warmer world. You are the one using terms like infantile and BS so maybe you are emotionally attached to colder winters from the past. That’s OK as long as you don’t let it influence your forecasting. 

I have offered many ideas about seasonal forecasts in too many threads to count. Just because I don’t offer a formal forecast each year isn’t a big deal. But I have successfully identified winter features in the fall that have worked out.

[40/70 Benchmark]

5 minutes ago, GaWx said:

Strong variability from winter to winter is not going away. It is just that this variability is from a 2F warmer base vs the 1970s.

Wonderfully stated and this is all I am arguing. It seems to me that @bluewave is arguing that the variability is going away, as least in terms of the pattern. I don't see that, but even it were to happen, it would take a long time to definitively reach that conclusion.

[Typhoon Tip]

I have a question regarding how NOAA determines it's anomalies wrt these SSTs.

Are these based on historical, empirical data averages alone?

This is different than RONI.  I'm asking because it occurs to me that this El Nino should have the CC -attribution negated from it..   I think RONI covers a bigger manifold of relative metrics? I'm just wondering if the warmer canvased SSTs then situating 1 C of real El Nino, might look like 1.5 but really just be the 1

 

 

[40/70 Benchmark]

12 minutes ago, bluewave said:

Variations whether you call them cyclical, teleconnections, or oscillations all exist in a warmer climate state than they used to. So they aren’t immune from alterations or adjustments to reflect the warmer world. You are the one using terms like infantile and BS so maybe you are emotionally attached to colder winters from the past. That’s OK as long as you don’t let it influence your forecasting. 

I have offered many ideas about seasonal forecasts in too many threads to count. Just because I don’t offer a formal forecast each year isn’t a big deal. But I have successfully identified winter features in the fall that have worked out.

I used pejorative terms because I don't see what my forecasting bias had to do with my belief that we will still have variations. Just seemed like you taking a jab. And as far as my emotions affecting my forecasts...I think that was the case years ago. But not today. I correctly forecasted some decent blocking last year, but it was negated by pretty unique circumstances out west. The only thing I love more than winter is jamming a correct forecast down the throat of my detractors en route to my own personal enrichment, so trust me....what I want most is to get it right.

[ORH_wxman]

9 minutes ago, 40/70 Benchmark said:

Wonderfully stated and this is all I am arguing. It seems to me that @bluewave is arguing that the variability is going away, as least in terms of the pattern. I don't see that, but even it were to happen, it would take a long time to definitively reach that conclusion.

Here is 2001-2015 winter temps compared to the previous 15 years....climate change was happening during all of this, yet much of the central and eastern US was colder in the mean. We wouldn't claim it is due to global cooling...we would claim it is due to natural variation on top of the underlying warming trend....it happened to overwhelm it during that period relative to the previous 15 years.

So yeah, it's not unreasonable at all to say that some of the warming the northeast has seen since 2015 is due to natural variation putting us in a more unfavorable pattern. I also reject that the pattern becomes more permanent. But we'll see. Maybe this is the one that actually does and all the others that failed to stay consistent (warm blobs, -AO due to sea ice, etc) were just flawed research.

 

[jm1220]

2 hours ago, 40/70 Benchmark said:

I feel like GW causes us to get stuck in more extreme patterns for longer durations of time....no research, just my anecdotal ob....this can sometimes lead to some extreme cold of duration, like '13-'14 and '14-15'. But more often than not, it means warmth, obviously....so maybe in that sense, the strong of warm NE winters relative to the rest of the nation IS due to GW to some degree, but that isn't permanent. 

The background state is getting warmer, so a cold pattern will be a little less cold and warmer patterns significantly warmer, but I think more research needs to be done on these marine heatwaves and how they affect the global patterns. It’s been plenty to near record cold in the Northwest in the past several winters. The W PAC marine heatwaves especially near Indonesia have been sticking the MJO in phases 4-6 repeatedly even when a Nino tries to develop. The PDO might be in a negative multi decade phase now but the waters near Japan are practically on fire and negates the warm water trying to move toward the W Coast. The warm water near Newfoundland probably helps cause further south NAO blocks when they do develop. I’m sure it’s not the only cause or 60% cause or whatever but it’ll be interesting to read what feedbacks they help drive since the oceans contain the vast majority of the global heat budget especially in the tropics. 

[40/70 Benchmark]

33 minutes ago, ORH_wxman said:

Here is 2001-2015 winter temps compared to the previous 15 years....climate change was happening during all of this, yet much of the central and eastern US was colder in the mean. We wouldn't claim it is due to global cooling...we would claim it is due to natural variation on top of the underlying warming trend....it happened to overwhelm it during that period relative to the previous 15 years.

So yeah, it's not unreasonable at all to say that some of the warming the northeast has seen since 2015 is due to natural variation putting us in a more unfavorable pattern. I also reject that the pattern becomes more permanent. But we'll see. Maybe this is the one that actually does and all the others that failed to stay consistent (warm blobs, -AO due to sea ice, etc) were just flawed research.

 

And I didn't think this regime would last forever because GW, either....so it has nothing to do with a bias. When it happens again...because it will, albeit warmer all around, I will say the same thing.

[griteater]

46 minutes ago, Typhoon Tip said:

I have a question regarding how NOAA determines it's anomalies wrt these SSTs.

Are these based on historical, empirical data averages alone?

This is different than RONI.  I'm asking because it occurs to me that this El Nino should have the CC -attribution negated from it..   I think RONI covers a bigger manifold of relative metrics? I'm just wondering if the warmer canvased SSTs then situating 1 C of real El Nino, might look like 1.5 but really just be the 1

 

 

CPC uses a moving 30 yr average for SST Nino region anomalies for ONI: Climate Prediction Center - Monitoring & Data: Ocean Niño Index Changes Description (noaa.gov)

"Due to a significant warming trend in the Niño-3.4 region since 1950, El Niño and La Niña episodes that are defined by a single fixed 30-year base period (e.g. 1981-2010) are increasingly incorporating longer-term trends that do not reflect interannual ENSO variability. In order to remove this warming trend, CPC is adopting a new strategy to update the base period.

There will be multiple centered 30-year base periods that will be used to define the Oceanic Niño index (as a departure from average or "anomaly"). These 30-year base periods will be used to calculate the anomalies for successive 5-year periods in the historical record

In real-time operations, the past 30-year base period (e.g. 1991–2020) will continue to be used to compute the departure from average. However, CPC will create an additional 30-year base period every 5 years (the next update will be at the beginning of 2026). When these 5 year updates occur, the ONI values over the most recent decade will change slightly because of the inclusion of more recent data."

[GaWx]

1 hour ago, 40/70 Benchmark said:

Wonderfully stated and this is all I am arguing. It seems to me that @bluewave is arguing that the variability is going away, as least in terms of the pattern. I don't see that, but even it were to happen, it would take a long time to definitively reach that conclusion.

Look no further than NYC for some big variability between adjacent winters just since 2010-1:

 

2010-1: 32.8

2011-12: 40.5

 Change was 7.7F

 

Even more impressive:

2014-5: 31.4

2015-6: 41

 The change from 2014-5 to 2015-6 was 9.6F, which is the 4th largest change on record between adjacent winters back to 1869-70.

[bluewave]

57 minutes ago, 40/70 Benchmark said:

I used pejorative terms because I don't see what my forecasting bias had to do with my belief that we will still have variations. Just seemed like you taking a jab. And as far as my emotions affecting my forecasts...I think that was the case years ago. But not today. I correctly forecasted some decent blocking last year, but it was negated by pretty unique circumstances out west. The only thing I love more than winter is jamming a correct forecast down the throat of my detractors en route to my own personal enrichment, so trust me....what I want most is to get it right.

Of course there are going to be variations. But the very nature of the variations can also change as the climate warms. Natural internal variability doesn’t exist in a vacuum.The -PNA -NAO patterns of the old days were colder and snowier in the Northeast than last winter. The -PNA trough last winter was weaker than was typical in the 50s to early 70s. So the issue last winter was the Greenland block building too far south in December. Those height rises east of New England were absent in the older era which  I showed earlier in this thread under -PNA -NAO patterns. So expanding the ridges associated with blocks alters the storm track enough to make a big difference in the Northeast. All it takes in our area is a 50 to 200 mile shift in the storm track. That may not be a big deal on a continental to hemispheric teleconnection map .But it’s everything if the storm tracks west of NYC instead of out near the benchmark for people in our area. 

[ORH_wxman]

4 minutes ago, bluewave said:

Of course there are going to be variations. But the very nature of the variations can also change as the climate warms. Natural internal variability doesn’t exist in a vacuum.The -PNA -NAO patterns of the old days were colder and snowier in the Northeast than last winter. The -PNA trough last winter was weaker than was typical in the 50s to early 70s. So the issue last winter was the Greenland block building too far south in December. Those height rises east of New England were absent in the older era which  I showed earlier in this thread under -PNA -NAO patterns. So expanding the ridges associated with blocks alters the storm track enough to make a big difference in the Northeast. All it takes in our area is a 50 to 200 mile shift in the storm track. That may not be a big deal on a continental to hemispheric teleconnection regieme. But it’s everything if the storm tracks west of NYC instead of out near the benchmark for people in our area. 

I think my main beef with your comparisons is assuming the Dec 2022 -NAO/-PNA pattern is the new norm or at least likely to be the dominant type of -NAO/-PNA pattern going forward....why are we ignoring the cold -PNA/-NAO pattern from late Jan to mid Feb 2021? Or what about the cold -NAO/-PNA pattern from mid Feb to early Mar 2019?

Dec 2022 looks like more an outlier to me than a new paradigm.

 

[ORH_wxman]

FWIW, here's the 2021 and 2019 patterns I was referring to

 

 

 

 

And the temp anomalies:

 

[40/70 Benchmark]

3 minutes ago, ORH_wxman said:

I think my main beef with your comparisons is assuming the Dec 2022 -NAO/-PNA pattern is the new norm or at least likely to be the dominant type of -NAO/-PNA pattern going forward....why are we ignoring the cold -PNA/-NAO pattern from late Jan to mid Feb 2021? Or what about the cold -NAO/-PNA pattern from mid Feb to early Mar 2019?

Dec 2022 looks like more an outlier to me than a new paradigm.

 

Yea, I obviously know GW is real and therefore it must be influencing the patterns, but my issue is that he is also making some large assumptions moving forward.

[bluewave]

31 minutes ago, ORH_wxman said:

I think my main beef with your comparisons is assuming the Dec 2022 -NAO/-PNA pattern is the new norm or at least likely to be the dominant type of -NAO/-PNA pattern going forward....why are we ignoring the cold -PNA/-NAO pattern from late Jan to mid Feb 2021? Or what about the cold -NAO/-PNA pattern from mid Feb to early Mar 2019?

Dec 2022 looks like more an outlier to me than a new paradigm.

 

I am not ignoring anything. But thank you for giving the opportunity to clarify a few points. The -PNA -NAO from January into February 2021 followed the strong +PNA earlier that winter. The south based block in December 2020 was mitigated to an extent by the +PNA. But the height rises east of New England forced the storm formation further west giving BGM the record 40” jackpot instead of closer to the coast. It also resulted in the flood cutter on Christmas. So when the PNA shifted later on, the weak +PNA trough which was over the SE in December moved into the 50/50 slot. So there was definitely a +PNA assist from earlier in the season for that -PNA -AO pattern. Two very strong south based blocks in December 2020 and 2022. Not to mention the other record south based blocks during different months of the year. The PNA trough was weaker in January as a result.

[40/70 Benchmark]

I think pinning tracks of individual storms on GW is where you are going to lose some people.

I'm just going to agree to disagree and leave it at that.